Issue link: https://maltatoday.uberflip.com/i/1401709
12 maltatoday | SUNDAY • 15 AUGUST 2021 OPINION "NOWHERE is safe." As the In- tergovernmental Panel on Climate Change (IPCC) warned in a recent report that climate change and its consequences are here to stay, is there still an opportunity to mit- igate some of the dangers and to get back to a place of relative safety for humanity? The challenge of surviving the next 50 years is now seen as a plan- et-wide existential crisis; we need to work together urgently, just to secure a short-term future for hu- man civilisation. Global weather patterns are violently disrupted: Greece burns; the south of Eng- land floods; Texas has had its cold- est weather ever, while California and Australia suffer apocalyptic wild fires. All of these violent, re- cord-breaking events are a direct result of rapid heating in the Arc- tic - occurring faster than in the rest of the world. A warm Arctic triggers new ocean and air cur- rents that change the weather for everyone. The only way to reverse some of these catastrophic patterns, and to regain a kind of stability in climate and weather systems, is "climate repair" – a strategy we call "reduce, remove, repair" – which demands that we make very rapid progress to net zero global emissions; that there is massive, active removal of greenhouse gases from the atmos- phere; and, in the first instance, that we refreeze the Earth's poles and glaciers to correct the wild weather patterns, slow down ice- melt, stabilise sea level, and break the feedback loops that relentlessly accelerate global warming. There are no either/or options. Reducing emissions About 70% of world economies have net zero emissions commit- ments over varying timescales, but this has come too late to restore climate stability. The IPCC has asked for accel- erated progress on this trajectory, but whatever happens, current emission rates of atmospheric greenhouse gases imply glob- al warming of 1.5℃ by 2030 and well over 2℃ above pre-industri- al level by the end of the century – a devastating outcome. In par- ticular, melting ice and thawing permafrost are considered inevi- table even if rapid and deep CO2 emissions reductions are achieved, with sea-level rise to continue for centuries as a result. In every area of the world, climate events will become more severe and more frequent, whether flooding, heat- ing, coastal erosion or fires. There are definitely important steps that can still reduce the scale of this devastation, including faster and deeper emissions reductions. However, this is not enough on its own to avert the worst. Together there is real evidence that the mas- sive removal of greenhouse gases from the atmosphere and solu- tions such as repairing the Earth's poles and glaciers could help hu- manity find a survivable way out of this crisis. Removing greenhouse gases Taking CO2 and equivalent greenhouse gases out of the atmos- phere, with the aim of getting back to 350ppm (parts per million) by 2100, involves creating new CO2 "sinks" – long-term stores from which CO2 cannot escape. Sinks operate at many scales, with forest planting, mangrove restoration, wetland and peat preservation all crucially important. Very large projects, such as the restoration of the Loess Plateau in China demonstrate scalable CO2 removal, with multiple add- on benefits of food production, bio-diversity enhancement and weather stabilisation. Habitat restoration can also make economic sense. In the Phil- ippines, mangrove is the focus of a cost-benefit analysis. Mangrove captures four times more carbon than the same area of rainforest, provides numerous ecosystem ser- vices and protects against flood- ing, conferring socio-economic benefits and significantly reducing the cost of dealing with extreme weather events. Big new carbon sinks must be created wherever safely possible, including in the oceans. Interven- tions that mimic natural process- es, known to operate safely "in the wild", are a workable starting point. Promotion of ocean pastures to re- store ocean diversity and fish and whale stocks to the levels last seen 300 years ago is one such possibil- ity – offering new sustainable food sources for humans, as well as con- tributing to climate ecosystem ser- vices and carbon sinks. In nature, sprinklings of iron-rich dust blow from deserts or volcanic eruptions, onto the surface of deep oceans, generating – in a matter of months – rich ocean pastures, teeming fish stocks and an array of marine wildlife. Studies of ocean kelp regeneration show the full range of real-life impacts, from increased protein sources for hu- man consumption, to restoration of pre-industrial levels of ocean biodiversity and productivity, and extensive carbon sequestration. Extending the scale and num- ber of ocean pastures could be achieved by systematically scatter- ing iron-rich dust onto target areas in oceans around the world. The approach is intuitively scalable, and could sequester perhaps 30 billion tons per year of CO2 if 3% or so of the world's deep oceans were to be treated annually. Large-scale carbon-sink creation of this kind is pivotal if the atmos- phere is to return to pre-industri- al CO2 levels. A billion tons per year of sequestration is the min- imum threshold coordinated by the Centre for Climate Repair at Cambridge given the intensity of the climate crisis. While the scale of intervention is sometimes called "geoengineering", the approach is closer to forest planting or man- grove restoration. The aim is to remove CO2 from the atmosphere using natural means, to return us to pre-industrial levels within a single generation. Repairing the planet The immediate challenge is to stabilise the planet, achieving a manageable equilibrium that gives a last chance to shift to renewa- ble energy and towards a circular global economy, with new norms in urban, rural and ocean manage- ment. "Repairing" systematically seeks to draw the Earth back from climate tipping points (which, by definition, cannot happen without direct effort), providing a support- ing framework in which "reduce" and "restore" can happen. Political and societal will is needed. The most urgent effort is to re- freeze the Arctic, interrupting a bleak spiral of accelerating ice loss, sea-level rise - and the accel- eration of climate change and vi- olent global weather changes that they cause. Arctic temperatures have risen much faster (and in- creasingly so) than global average temperatures, when compared with pre-industrial levels. Figure 1 shows this clearly from 1850 to the present day. Melting Arctic ice embodies a powerful feedback force in climate change. White ice reflects the Sun's energy away from the Earth before it can heat the surface. This is known as the albedo effect. As ice melts, dark-blue seawater ab- sorbs increasing amounts of the Sun's energy, warming increases, and ever-larger areas of ice disap- pear each summer, expanding the acceleration. Arctic temperatures govern winds, ocean currents and weather systems across the globe. A tipping point is passing: sea- ice loss is becoming permanent and accelerating; Greenland ice will follow and will eventually raise global sea-levels by over seven me- tres. Total loss may take centuries but, decade by decade, there will be relentless incremental impacts. By mid-century the melting will be irreversible, and sea-level rise alone will leave low-lying coun- tries like Vietnam in desperate circumstances, with reductions to global rice production a certainty, many millions of climate refugees and no obvious pathway forward for such nations. The rapid Arctic temperature increase is matched by the rapid and accelerating loss in minimum (summer) sea-ice volume (Figure 2), which further accelerates the temperature rise in a spiral of rein- forcing feedback loops. It is vital to pivot the world back from this ice-melt tipping point, and to repair the Arctic as rapidly as possible. Marine cloud bright- ening in which floating solar-pow- ered pumps spray salt upwards to brighten clouds and create a reflective barrier between the Sun and the ocean, is known to cool ocean surfaces and is a promising way to promote Arctic summer cooling. It mimics nature, and can be scaled up or down in a flexi- ble way. Studies of marine cloud brightening, its climate impacts and interactions with human sys- tems, are underway. As with promotion of ocean pastures, such solutions must be critically analysed, but there is no longer any doubt of their crucial importance. What we do in the next five years determines the viability of human- ity's future. Even if we narrow our aspirations to "survival", fixing on a timescale of 50 years or so, the challenges are daunting. Human- ity deserves better. We know what to do to be able to imagine thousands of years of human civilisation ahead, as well as behind us. Climate repair: three things we must do now to stabilise the planet David King & Jane Lichtenstein Jane Lichtenstein and David King are associate and founder respectively at Centre for Climate Repair, University of Cambridge Decline in annual minimum Arctic Sea ice volume 1980-2020. Provided by Nerilie Abram using IPCC data, ANU, Australia, 2021